Lock-up device



March 22, 1960 w. B. BURGARD 2,929,323

LOCK-UP DEVICE Filed June 3, 1959 3 Sheets-Sheet 2 1N VEN TOR. 4 ma /AM 8. BURG'A R0 M, My @MN A TTORNEYS.

March 22, 1960 w. B. BURGARD LOCK-UP DEVICE 3 Sheets-Sheet 3 Filed June 3, 1959 -U- z z O 8$ INVENTOR. MAL IA M 8. BURGARD BY. W, M r @aa,

United States l atent LOCK-UP DEVICE William B. Burgard, East Aurora, N.Y., assignor to J. W. Clement Company, Buffalo, NY.

Application June 3, 1959, Serial No. 817,925 5 Claims. (Cl. 101415.1) I

This invention relates to a fastening means, and more particularly to means for clamping a flexible web to and/or around a back-up block or cylinder or the like for mounting flexible printing plates 'or abrasive webs. Such devices are often referred to as lock-ups.

One object of the invention is to provide an improved lock-up device which will more positively grip and retain a web and may be more precisely adjusted to exert the proper degree of tension n the web and to more exactly. position said web on the back-up means, compared to devices of the prior art.

Another object of the invention is to provide a lockup means as aforesaid which will successfully resist any tendency of the mounted web to become loosened or misaligned as a result of the rotational and other stresses to which, for example, printing or abrading devices are subject while in operation.

Other objects and advantages will appear from the detailed description hereinbelow and the accompanying drawing wherein:

Fig. 1 is a front elevational view showing a lock-up device of the invention mounted in a printing cylinder.

Fig. 2 is an end elevational view of the arrangement of Fig. 1 with a portion thereof shown in section along line lIII of Fig. 1.

Fig. 3 is a sectional perspective view on reduced scale depicting the operation of mounting a printing plate on a cylinder by means of lock-up devices of the invention.

Fig. 4 is a fragmentary sectional view taken on line IV-IV of Fig. 2.

F Fig. 5 is a sectional view taken along line VV of Fig. 6 is a fragmentary sectional view taken on line VI-Vi of Fig. 5.

Fig. 7 is a perspective view of certain components of the device in disassembled relation; and

Fig. 8 is a detailed view of a component of the device,

The lock-up device of the invention is illustrated and described herein as being mounted on a printing cylinder 10 which may be adapted for mounting in a rotary printing press (not shown) by means of axle portions 11, 11 extending from each end thereof. End plates 12,12 are fitted to each end of the cylinder and secured thereto by bolts 13. The cylinder 10 is longitudinally milled out or otherwise recessed to receive one or more lock-up housing bars 14 in slip-fit relation (the use of twosuch bars being shown herein); the cylinder being bored and tapped to accommodate bar retaining bolts 16. Each housing bar 14 is counterbored as indicated at 17 to allow the bolts 16 to be recessed therein, and a T-shaped slot 18 runs the full length thereof.

In the form of the invention shown in the drawings, each housing bar 14 is designed to hold two sets of plate locking assemblies, each assembly including a gripping strip 20 and a cam plate 25. As best seen in Fig. 7, each gripping strip 20 has a relieved front edge portion 21, a plate retaining slot 22 running the length of the 2,929,323 Patented Mar. 22, 19

a ICE gripping strip adjacent the relieved portion 21, andcam grooves 23 running diagonally therein. The gripping strips 20 are of the same length as the cylinder and are restrained from lengthwise movement therein by the end plates,,12, 12. The cam plates 25, 25 fit flatwise into the inner branch portions of the recesses provided by the T-shaped slot 18 and are thereby restrained from lateral movement but are made somewhat shorter than the housing bar to permit movement in their lengthwise directions. One face of each cam plate 25 is provided. with cams 26 located and dimensioned to interfit with the cam grooves 23 of the gripping strip 20. At one end of each cam plate 25, it is provided with an internally threaded lug 28 (Fig. 7) and one end of the housingbar 14 is recessed as indicated at 30 (Fig. 4) to slidably accommodate the lugs 28 therein. Thus it will be appreciated that when two gripping strips 20, 20 are placed back to back and a cam plate 25 is located against each gripping strip with the cams .26 interfitting with the cam grooves 23, this subassembly may be endwise inserted into the slot 18 with lugs'28, 28 sliding into the recesses 30, 30. Thus, with housing bar 14 secured in the cylinder by the screws 16 and the end plates 12,12 in place, any movement of the cam plates 25 must be in the direction of their longitudinal axes while movements of the grippingstrips 20 are restricted to directions transverse of their longitudinal axes.

As best seen in Figs. 1, 2 and 5, the lock-up device of the invention may be actuated by means of actuating screws 32, 32 which pass through and rotate freely within bores provided in one of the end plates 12 and are threadably engaged with the lugs 28 of the cam plates 25. The screws 32, are provided with stop collars 34 (Figs. 5, 8); spaced from the head portions 33 to form annular grooves therebetween. A stop plate 36 is bolted to the end plate as by means of machine screws 37, and is provided with a flange portion 38 which fits between the head 33 and the collar 34 of each actuating screw,32. The screws 32 are thereby prevented from moving axially, and therefore rotary motions of the screws 32 will cause translational motions of the cam plates 25. As the gripping. strips 20 can move only transversely of their longitudinal axes, the cooperating diagonally oriented cam ledges 26 and slots 23 will cause the front edges of the gripping plates to move in or out of the slot 18, depending on the direction in which screws 32 are rotated.

Thus a printing plate as shown at 40 provided with a raised ridge portion 42 at each end may be quickly and securely attached to the printing cylinder simply by turning the actuating screw to run the. front edge of a gripping strip. out beyond the cylinder surface, inserting the ridge portion 42 of one end of the plate into the retaining groove 22, and retracting the gripping plate into the slot. The process is then duplicated for the other end of the printing plate. Thus the ends of the plate will be firmly held between the wall of the slot 18 on one side and the gripping stripf20 on theother; witlith'e ridge 42 locked in the groove 18. It will be apparent that the lock-up device may be adjusted to exert the exact degree of tension desired on the printing plate. apparent that any number of the lock-up devices may be ,used, depending on what part of the cylinder it is de- It will also be i ribbed end portion of a web member to be mounted upon and tautened over said back-up device, said lock-up device comprising a housing bar sectionally dimensioned to slip-fit into said elongate recess and to be disposed therein flush with the adjacent surface of said back-up device, said housing bar having a T-sectioned slotway extending longitudinally thereinto from the exposed surface thereof, a cam plate slip-fitted into each of the internal branch portions of said slotway and lengthwise shiftable therein, a pair of retaining strips slide-fitted in juxtaposed relation between said cam plates and having front edge port'ions formed with hook devices for engaging the ribbed end portions of the webs'to be mounted, cooperating cam i'neans interconnecting adjacent cam plates and retaining strips arranged to causesaid retaining strips to move inwardly or outwardly of said slotway responsive to lengthwise shifting of said cam plates, and screw means en gaging said cam plates and bearing against said device whereby rotation of said screw means will displace said camplates lengthwise and cause said retaining strips to be c'ammed inwardly or outwardly of said slotway .for alternative engagement-and tautening of said web and release thereof.

2'. In combination, a printing press cylinder having a surface portion formed with an elongate recess and a printing plate lock-up device fitting into said recess adapted to engage a ribbed end portion of a plate to be mounted upon and tautened over said cylinder, said lock-up device comprising a housing bar sectionally dimensioned to slip-fit into said elongate recess and to be disposedtherein flush with the adjacent surface of said cylinder, said housing bar having a T-sectioned slotway extending longitudinally thereinto from the exposed surface thereof, a cam plate slip-fitted into each of the internal branch portions of said slotway and lengthwise shiftable therein, a pair of retaining strips slide-fitted in juxtaposed relation between said cam plates and having front edge portions formed with hook devices for en- 'gaging the ribbed end portions of the plates to be mount- 'ed, cooperating cam means interconnecting adjacent cam plates and retaining strips arranged tocause said retainstrips to move inwardly or outwardly of said .slotway responsive to lengthwise shifting of said cam plates, and screw means engaging said cam plates and bearing against said cylinder whereby rotation of said screw means will displace said cam plates lengthwise and cause said retaining strips to be cammed inwardly oroutwardly of said slotway for alternative engagement and tautening of said plates and release thereof. I

3. In combination, a printing platen having a surface portion formed with an elongate recess and, a plate lockup device fitting into said recess adapted to engage a ribbed end portion of a plate member to be mounted upon and tautened over said platen, said lock-up device comprising a housing bar sectionally dimensioned to slipfit into said elongate recess and to'be disposed therein flush with the adjacent surface of said platen, said housing bar having a T-sectioned slotway formed longitudinally thereinto'from the exposed surface thereof, a cam plate slip-fitted into each of the internal branch portions of said slotway and lengthwise shiftable therein, a pair of retaining strips slide-fitted in juxtaposed relation between said cam plates and'having front edge portions formed with book devices for engaging the ribbed end portions of the plates to be mounted, cooperating cam means interconnecting adjacent cam plates and retaining strips arranged to cause said retaining strips to move inwardly or outwardly of said slotway responsive to lengthwise shifting of said cam plates, and screw means engaging said cam plates and bearing against said platen whereby rotation of said screw means will displace said cam plates lengthwise and cause saidretaining strips to be cammed inwardly or outwardly of said slotway for alternative engagement and tautening of said plates and release thereof.

4. In combination, a printing platen having a surface portion formed with an elongate recess and a plate lock-up device fitting into said recessradapted to engage a ribbed end portion of a plate member to be mounted upon and tautened over said platen, said lock-up device comprising a housing bar sectionally dimensioned in slitfit into said elongate recess and to be disposed therein flush with the adjacent surface of said platen, said housing bar having a slotway formed longitudinally thereinto from the exposed surface thereof, a cam plate slip-fitted into said slotway and lengthwiseshiftable therein, a retaining strip slide-fitted in juxtaposedrelation between said cam plate and having a front edge portion formed with hook device for engaging thev ribbed end portion of the plates to be mounted, cooperating cam means interconnecting said camplate and retaining strip ar ranged to cause said retaining strip to move inwardly 'or outwardly of said slotway responsive to lengthwise shifting of said cam plate, and screw means engaging said cam plate and bearing against said platen whereby rotation of said screwf meanswill displace said cam plate lengthwise and cause said retaining strip to be cammed inwardly or outwardly of said slotway for alternative engagement and tautening of said plate and release thereof. 1 t

5. In combination, a back-up device and a web lockup device mounted thereon and adapted to engage a ribbed portion of a' web memberto bemounted upon and tautened over said back-up device, said lock-up device comprisinga housing bar having a slotway extending thereinto, a cam plate slip-fitted into'said slotway and lengthwise shiftable therein, a retaining strip slidefitted in juxtap'osedrelation with. said cam plate having a front edge portion formed with a hook device for engaging the ribbed'end .portionof the web to be mounted cooperating cam means interconnecting said cam plate and retaining strip arranged. to cause said retaining strip to move inwardly or outwardly of said slotway responsive to lengthwise shifting of said cam plate, and means engaging said carn plate and operable to displace said cam plate lengthwise and to cause said retaining strip to be cammed inwardly or outwardly of said slotway for alternative engagement and tautening of said web and release thereof.

I No references cited. 

